(a) Field of the Invention
This invention relates to a prosthesis for a limb amputee who has lost his knee or a portion of the thigh and femur above the knee, and to such a prosthetic or robotic knee joint which can be myoelectrically controlled and which can be driven by a conventional power source.
(b) Discussion of the Prior Art
Heretofore there have been a variety of prostheses that are controlled myoelectrically using neural signals, and responding bioelectrically. These devices and systems for controlling artificial limbs are described in U.S. Pat. No. 3,735,425 to Hoshall et al; U.S. Pat. No. 4,878,913 to Aebischer et al; U.S. Pat. No. 3,501,776 to Beeker et al; U.S. Pat. No. 3,491,378 to Ioffe et al; and U.S. Pat. No. 4,792,338 to Rennerfelt. While the above mentioned patents discuss broadly methods and systems for operating a prosthesis, and more specifically for controlling an artificial arm or hand, none of the above-mentioned patents disclose an improved knee prosthesis which allows the user of the prosthesis to simulate natural positions and motions of a normal human knee.
In U.S. Pat. No. 3,453,663 to Minor and U.S. Pat. No. 3,800,334 to Friberg, two different types of artificial legs are shown for above-knee amputees. The artificial legs include a thigh section, a shank section, a foot section, an ankle joint, and a pivotal knee joint. Each of these artificial legs incorporates a single pivot to simulate the movement of the knee and therefore do not allow or provide for the complex movements of a normal knee into the artificial leg.
In U.S. Pat. No. 4,614,518 to Lehneis et al an artificial limb is disclosed having two limb members connected by a knee joint provided with rotator members. The rotator members are cylindrical with one forming a rotatable sleeve about the other. The rotator members rotate about a single pivot and this artificial limb does not allow or provide for the complex movements necessary to simulate the operation of a normal knee.
In U.S. Pat. No. 4,379,350 to Munny a prosthetic joint for knee and above-knee amputees is disclosed having an articulated joint with an arcuate rack, a rectilinear rack, and a pinion mounted on a slide and engaging the two racks. This structure of the articulated joint allows for a rotary and sliding movement of the knee. The type of knee movement provided by this prosthetic joint fails to simulate the natural rocking motion of the human knee.
None of the above-mentioned patents describe or disclose teachings similar to the subject robotic knee and its unique features and modes of operation as described herein.